Image SEO Checklist – Free Template
🖼️ Image SEO Checklist
15 Essential Steps to Faster, Rankable Sites
Created by Victor Marangu
maranguvictor.online | brandscapestudio.online
maranguvictor.online | brandscapestudio.online
📋 How to Use This Checklist
Work through each step as you optimize images. Check off completed items, add notes for your specific situation, and track your progress. Focus on high-impact items first (marked in red) for fastest results.
📁 Naming & Structure
1. Use Descriptive, Keyword-Rich File Names
Rename files before upload. Use “blue-running-shoes.jpg” not “IMG_1234.jpg”
MEDIUM IMPACT
⏱️ 30 sec per image
2. Organize Images in Logical Folder Structures
Create hierarchy like /images/blog/2024/ or /images/products/category/
LOW IMPACT
⏱️ One-time setup
3. Use Hyphens to Separate Words
Always use hyphens (-) not underscores (_) in file names
LOW IMPACT
⏱️ 15 sec per image
✍️ Alt Text & Metadata
4. Write Descriptive, Accurate Alt Text
Describe what’s in the image clearly. Keep under 125 characters. Example: “woman in yellow rain jacket hiking through misty forest trail”
HIGH IMPACT
⏱️ 1 min per image
5. Include Primary Keyword in Alt Text (When Relevant)
Only use your target keyword if it naturally describes the image. Don’t force it. Use on 1-2 images per page max.
MEDIUM IMPACT
⏱️ Included in Step 4
6. Add Title Attributes Where Appropriate
Optional: Add title attribute for tooltips on hover. Don’t duplicate alt text.
LOW IMPACT
⏱️ 30 sec per image
7. Include Image Captions for Context
Add visible captions for photos, charts, data visualizations. Captions get read more than body text.
MEDIUM IMPACT
⏱️ 1 min per image
🗜️ File Optimization
8. Compress Images Without Quality Loss
Run all images through compression. Target under 100KB. Use 80-85% quality for photos. Tools: TinyPNG, Squoosh, ShortPixel
HIGH IMPACT
⏱️ 30 sec per image
9. Resize Images to Display Dimensions
Never upload 3000px images that display at 800px. Resize to max display size first.
HIGH IMPACT
⏱️ 30 sec per image
10. Choose the Right Format
WebP for photos (best compression), JPEG for fallbacks, PNG for transparency, SVG for logos/icons
MEDIUM IMPACT
⏱️ 15 sec per image
11. Use Next-Gen Formats with Fallbacks
Implement <picture> element to serve WebP with JPEG/PNG fallbacks for older browsers
MEDIUM IMPACT
⏱️ 2 min per implementation
⚙️ Technical Implementation
12. Implement Lazy Loading for Below-Fold Images
Add loading=”lazy” to images below the fold. Don’t lazy load hero images or immediately visible content.
HIGH IMPACT
⏱️ 5 min site-wide
13. Use Responsive Images with Srcset
Serve different image sizes for different screen dimensions. Generate 3-4 sizes (mobile, tablet, desktop, large desktop)
HIGH IMPACT
⏱️ 3 min per template
14. Specify Width and Height Attributes
Always include width and height in image tags to prevent CLS (Cumulative Layout Shift). Critical for Core Web Vitals.
HIGH IMPACT
⏱️ 30 sec per image
15. Create and Submit an Image Sitemap
Generate image sitemap (or include in main XML sitemap) and submit via Google Search Console
MEDIUM IMPACT
⏱️ 30 min one-time
📊 Quick Priority Reference
| Priority | Step | Why It Matters |
|---|---|---|
| 🔴 START HERE | Step 8: Compress Images | Biggest page speed impact – can reduce load time by 50%+ |
| 🔴 START HERE | Step 4: Write Alt Text | Accessibility + SEO + image search rankings |
| 🔴 START HERE | Step 12: Lazy Loading | Dramatically improves initial page load speed |
| 🔴 START HERE | Step 14: Width/Height | Prevents CLS – direct Core Web Vitals impact |
| 🟡 Do Next | Steps 9, 10, 13 | Optimize file sizes and mobile performance |
| 🟢 Polish | All remaining steps | Complete optimization for maximum results |
🛠️ Recommended Tools
- Compression: TinyPNG, Squoosh (Google), ShortPixel
- WordPress Plugins: Smush, Imagify, EWWW Image Optimizer
- Format Conversion: Squoosh, CloudConvert
- Testing: Google PageSpeed Insights, Lighthouse (Chrome DevTools)
- Bulk Processing: ShortPixel, Kraken.io